High Performance Trays Enhanced Deck and Downcomer Technology

Transcription

1 High Performance Trays Enhanced Deck and Downcomer Technology

2 Sulzer Chemtech Separation Technology Your partner in separation and mixing technology The highest level of application know-how Our team provides state-of-the art expert know-how for more than 500 applications in 100 processes, this enables us to optimize the performance and your installation. Fast and reliable turnaround services We don t shut-down, when you shut-down. You can rely on Sulzer professionals, expertise and procedures to get you back and running in the shortest possible time. Comprehensive engineering and technology services We provide a full scope of associated engineering and technology services to optimize or trouble-shoot your installation. Naphtha Kero Diesel A broad range of innovative and high-performing products Our more than 200 products cover a wide range of needs in the field of separation and mixing technology. They have proven their performance in more than 100'000 columns, 50'000 gas/liquid or liquid/liquid separators and 100'000 static mixers in operation worldwide. MellapakPlus Packing Often copied, never equaled UFMPlus trays One of the best high performance trays ever tested at FRI NeXRing The next big thing in random packing SMV static mixer High mixing efficiency combined with large turn-down processing capabilities Dusec Plus Coalescer High performance liquid/liquid coalescer 2

3 High Performance Trays UFMPlus TM and VGPlus TM 6 Anti-fouling trays 9 Shell HiFi TM trays 10 Shell ConSep TM trays 12 Mechanical features and services 14 We understand the ever increasing requirement for both reliability and performance of your process equipment. To meet these challenges, you can rely on our innovative, industry-leading products and expertise. Our extensive tray portfolio ranges from single pass to multi-downcomer as well as conventional to high-performance, including the latest technology in ultra-system limit trays. All designs are tailored to meet the exact requirements of your specific application. For your most demanding applications, our high performance trays include VGPlus trays with MVG decks and enhanced downcomer technology as well as the newest trays, UFMPlus with UFM valves. The UFM valve is an industrially proven, advanced movable mini valve providing the highest efficiency and capacity. For fouling applications, Sulzer has developed a new high performance anti-fouling valve UFM AF, which provides high capacity in addition to its superior fouling resistance. This portfolio has been greatly enriched since 2000 by our technology alliance with Shell Global Solutions, and also includes Shell high performance trays such as the Shell HiFi trays, ideal for high liquid load applications, and Shell ConSep trays with proven ultra-system capabilities. Tray portfolio Sulzer technology Sulzer-Shell alliance Conventional trays Chordal downcomer High performance trays Multi downcomer High performance trays Floating valves Other orifices Enhanced deck Enhanced deck and downcomer BDH / BDP Bubble Cap Floating valves VGPlus Round valves Sieve UFM UFMPlus Shell HiFi Plus Shell HiFi Shell Calming Section Plus Shell Calming Section (CS) Fixed valves Counter flow trays Fixed valves Dual flow high performance trays XVG Dual Flow MVG SVG Baffle MMVG SVG-H Shower Deck UFM AF Shell CS Grid Ultra-system limit high performance trays Shell ConSep LVG Disc and Donut Slit Trays High performance trays featured in this brochure 3

4 Leading Tray Technology In the 1820s, an early version of bubblecaps trays were introduced for continous distillation towers. In the 1950s, valve trays were developed, providing higher capacity and better efficiency over a wider operating range. The modern valve tray, a rectangular float valve tray, was first installed by I.E. Nutter in By 1956, different variations of round valves had surfaced. Bubblecaps in Sulzer's tray portfolio Round valve Caged valve BDH TM Rectangular float valve Modern 1-pass Sieve tray V-Grid Fixed valves from left to right: SVG TM, MVG TM and MMVG TM Fixed valves In the 1830s, sieve trays were developed, offering higher capacity despite design simplicity. In 1998, Sulzer acquired Nutter Engineering, incorporating the well-acclaimed BDH TM rectangular float valve and V-Grid fixed valves into Sulzer's tray product portfolio. 4

5 In 2000, Sulzer formed a technology alliance with Shell Global Solutions providing a full range tray product portfolio from one source. These include Shell Calming Section TM (Plus) trays, Shell HiFi (Plus) trays and ultra-high capacity Shell ConSep trays. In 2012, Sulzer launched a new valve product UFM, a movable valve which provides higher capacity and a wider operating range than conventional valves. In 2014, Sulzer launched UFMPlus, a high performance tray with a UFM deck and enhanced downcomers. In 2017, Sulzer also developed a high capacity anti-fouling valve UFM AF for fouling applications. Enhanced decks with UFM AF valves are part of UFMPlus tray family. Shell HiFi TM tray Shell ConSep tray In 2000, Sulzer introduced high performance VGPlus trays which provide higher capacity with the combination of enhanced downcomers and optimized tray layout. Sulzer has also introduced high performance VG AF antifouling trays, part of VGPlus tray family, featuring large fixed and push valves, and fouling resistant outlet weirs. Sulzer s 6-pass VGPlus high performance trays were successfully installed in several C3 Splitters and are performing beyond expectations. 6-pass trays are a natural progression after 4-pass trays for large diameter columns (typically > 6 m) with high liquid loads. 5

6 UFMPlus and VGPlus UFMPlus and VGPlus, are Sulzer s high performance chordal downcomer trays. They offer industry proven and validated advanced tray technology for today s market. Enhanced downcomers A main feature of Sulzer UFMPlus and VGPlus trays is the use of high performance downcomers such as highly sloped, Truncated, StepArc (stepped), ModArc and our latest Prism downcomers. These downcomer designs maximize the tray deck area by optimizing the downcomer bottom area, thereby increasing vapor handling capacity and reducing pressure drop and backup. Enhanced decks Sulzer high capacity trays can be equipped with high capacity fixed valves or float valves. UFMPlus trays use high capacity UFM float valves while VGPlus trays are equipped with high capacity fixed valves such as MVG or MMVG. Redirecting and froth promoting devices such as push valves and baffle bars, enhance the vapor/ liquid interaction on the tray deck. Liquid flow study of conventional trays 2-pass UFMPlus tray equipped with Prism downcomers, UFM and push valves. Liquid flow study of VGPlus with baffle bars Truncated downcomer StepArc downcomer ModArc downcomer 6

7 UFMPlus trays UFMPlus trays are enhanced downcomer trays with high capacity UFM float valves and innovative periphery valves which further boost the performance of the trays. UFM valves are an advanced type of movable mini-valve which maximize the hydraulic capacity, the separation efficiency, and the operating range of fractionation trays. The "Umbrella" shape of UFM valves reduces the jetting momentum of the released vapor which maximizes the contact area of vapor and liquid on the tray deck and promotes uniform mixing and minimizes entrainment. The UFM tray deck offers better turndown capability than a fixed valve tray, i.e. up to 5:1. VGPlus trays VGPlus trays are enhanced downcomer trays with high capacity MVG or MMVG fixed valves. MVG valves provide higher capacity compared to standard sieve or conventional valves, while providing higher efficiency and lower pressure drop per theoretical stage. The MVG tray deck offers better turndown capability than a sieve tray, i.e. up to 3:1. MMVG valves are used where extremely high vapor capacity or a very low pressure drop is required. The smaller size opening compared to MVG results in up to 7% additional capacity. FRI VALIDATION Sulzer UFM valves have been tested at FRI, in the cyclohexane/n-hexane system at 1.6 bar and in the ortho-xylene/ para-xylene system at 1.0 bar. The UFM valves showed a 30% increase in efficient capacity when compared to conventional valves, making the UFM tray one of the highest capacity trays ever tested at FRI, at these conditions. FRI VALIDATION Sulzer VGPlus trays have been tested at FRI, in the iso-butane/ n-butane system at 7 and 11 bar. The VGPlus tray is one of the best performing trays ever tested, delivering up to 10% higher capacity than some other tested competitor's high performance trays. KEY AREAS OF APPLICATION Refinery: Main Fractionators and Gas Plants Olefins: Deethanizers, Depropanizers, Debutanizers, Deisobutanizers, SuperFractionators: C2 and C3 Splitters Aromatics: Xylene Splitters, Xylene Rerun, Raffinate Columns 7

8 Sulzer "Plus" Technology Case study - Revamp of deisobutanizer with VGPlus trays A refinery deisobutanizer column, upstream of an HF alkylation unit, was identified to be the bottleneck of the capacity expansion. Feed-3 Feed-2 1 PC FC LC Fuel Gas This deisobutanizer column of ID 2.96 m was originally equipped with 56 2-pass conventional round valve trays. A process study highlighted that the throughput could be almost doubled by retrofitting the tower with high performance trays. Feed-1 FC LC TC New VGPlus HPTrays FC Iso-C4 Revamp objective: Maximize the production of ic4 Minimize nc4 in top product: <3 wt% Maximize ic4 recovery: >94 wt% Revamp solution: Sulzer VGPlus high performance trays with MVG fixed valves ModArc side downcomers Froth enhancers: push valves Test run was performed at 143% of the pre-revamp capacity due to shortage of feedstock. To further load the tower, the reflux ratio was increased till maximum reboiler duty: the production of ic4 increased by 57%, with a nc4 impurity as low as 0.9 wt% and ic4 recovery over 98 wt% leading to a tray efficiency over 93% even at flooding close to 90%. From Iso-Stripper Reboiling Fluid FC 56 Before revamp Design Test run Feed flow rate 100% 191% 143% Top ic4 flow rate 100% 193% 157% Reflux ratio NA Tray efficiency NA 86% > 93% nc4 impurity > 3 wt% 3 wt% < 0.9 wt% ic4 recovery < 94 wt% 94 wt% > 98 wt% Flooding NA 80% 89% LC FC n-c4 Sulzer's experience - 6-pass VGPlus trays for new C3 splitters Three new C3 Splitters, each designed with pass VGPlus high performance trays. For columns with large diameters, 6-pass trays provide extensive weir length to handle the high liquid loads. The multiple pass design also avoids excessively long flow path lengths to mitigate undesirable liquid flow gradients on the tray decks. Enhanced downcomers are utilized to maximize the bubbling area for mass transfer. Sulzer design: Sulzer VGPlus high performance trays with MVG fixed valves ModArc side downcomers Froth enhancers: push valves 8

9 Anti-Fouling Trays UFM AF UFM AF is the latest addition to our fixed valve portfolio. This enhanced valve is part of the UFMPlus tray family, developed for fouling service. UFM AF is a large size valve which provides excellent fouling resistance, especially when designed with the following antifouling features on the tray: Modified outlet weirs: stepped or sloped Push valves VG AF VG AF (anti-fouling) trays are part of the VGPlus tray family and especially designed for fouling services. Tray decks of VG AF will either be with SVG, our standardfouling valve, or XVG, our extra large V-Grid developed especially for severe fouling services. Other anti-fouling tray design features like enhanced outlet weirs and push valves will also be applied. UFM AF is a premium anti-fouling valve with very high efficient capacity. Enhanced downcomers can be applied to UFM AF trays for even higher capacity, if required. 2-pass VG AF trays with V-Grid, sloped outlet weir and push valves. KEY AREAS OF APPLICATION UFM AF Primary fractionators in ethylene plant Stripping section of CDU and VDU Coker main fractionators Heads and dry columns of acrylonitrile plant PVC slurry strippers Beer columns Case study - Revamp of acrylonitrile heads and dry column to VG AF Acrylonitrile (ACN) heads and dry column was revamped from round valves trays to Sulzer VG AF anti-fouling trays for higher performance and longer run length. This ACN column was originally equipped with 62 1-pass conventional round valve trays. From Dec. Recovery Column BRINE HCN Tower Revamp objective: Increase capacity by 25% Maximize acrylonitrile recovery: > 91 wt% Maximize run length: > 6 months CW Quench Tower Revamp solution: Sulzer VG AF anti-fouling trays with SVG fixed valves Stepped outlet weirs Froth enhancers: push valves As a result of the revamp with VG AF trays, the column capacity increased by 25%. The ACN recovery improved to 95% and the run length increased to more than 11 months. Product Tower Before revamp After revamp Feed 100% 125% ACN production 100% 130% ACN recovery 91 wt% 95 wt% Tray efficiency 70% 74% Run length [months] 4 >11 9

10 Shell High Performance Trays Shell HiFi Plus trays Shell HiFi trays are fractionation trays equipped with multiple envelope downcomers, oriented offset to the tray's center line. They are supported on a 360 support ring and central major beams, without the need of the downcomer bolting bars. For a given column diameter, they allow for: Highest number of passes Large downcomer area Long weir length High hydraulic capacity Low tray spacing High NTS per column height HiFi Plus tray with MVG valves The HiFi Plus trays are an enhanced version featuring advanced valves (i.e. MVG, MMVG, UFM) to further boost the tray deck performance, and/or the Crown Inlet Device CID to maximize the downcomer capacity as well. FRI VALIDATION Shell HiFi trays, with tray spacings of 305 mm and 610 mm, have been tested at FRI, in the iso-butane/ n-butane system at 11, 21 and 28 bar. As compared to 1-pass round valve trays with truncated downcomers, Shell HiFi trays of same tray spacing, exhibit up to 40% higher capacity. KEY AREAS OF APPLICATION Refinery: Main fractionators' PA and stripping sections Olefins: Deethanizers, Depropanizers, Debutanizers, Deisobutanizers, SuperFractionators: C2 and C3 Splitters Aromatics: Xylene Splitters, Xylene Rerun, Raffinate Columns Gas Sweetening: absorbers, regenerators Sulzer's experience - New Shell HiFi trays for crude distillation Revamp of top 3 pumparound trays of a crude distillation column from conventional trays to Shell HiFi trays which offer longer weir length to handle the higher liquid loads. Due to large column diameter of 9.6 m, two beams were required for each tray. Revamp design: Shell HiFi trays with 2 beams design 21 HiFi downcomer boxes Long weir length > 110m 10

11 Case study - Revamp of C2 Splitter to Shell HiFi Plus trays A C2 Splitter (3.96 m I.D.), was revamped from 153 competitor's Multi-Downcomer trays to 123 Sulzer HiFi trays for improved C2 Splitter performance higher capacity and stringent product purity. Revamp objective: Increase capacity by 25% Ethylene purity: wt% Revamp solution: Shell HiFi Plus trays with MMVG fixed valves HiFi downcomer boxes Long weir length > 23 m During the performance test run when the column was artificially loaded up for the highest throughput, steady operation was observed with a useful capacity around 95%, and a measured ethylene purity of 99.98%. A tray efficiency of 79% was achieved. Full assembly during trial layout at workshop Design Test run Ethylene purity 99.96% 99.98% Tray efficiency 80% 79% Case study - New xylene rerun column with Shell HiFi Plus trays A new xylene rerun column, of ID 8.3m, was designed with 117 Shell HiFi Plus trays. The design included 1 lattice beam for every 2 trays. Sulzer design: Shell HiFi Plus trays with MVG fixed valves 10 HiFi downcomer boxes Long weir length > 60m Although actual production was less than maximum loads, the reflux ratio was higher than design due to higher amount of impurities in feed. The Shell HiFi Plus trays performed well, providing higher capacity while meeting the process requirements. This column was compared with a similar column in client's plant, equipped with competitor's multi-downcomer trays, and proved to be better in terms of relative energy consumption and product recovery. Process requirements: C9+ impurity in distillate: <300 ppmwt O-xylene recovery in distillate: >99.0 wt% Design Actual operation Feed 125% 100% Reflux / feed ratio [mass] Min. recovery 99.0% 99.5% Tray efficiency 73% 74% 11

12 Shell Ultra-System Limit High Performance Trays Shell ConSep trays The Shell ConSep trays are one of the highest capacity fractionation trays available on the market, offering up to 80% additional capacity over conventional trays without any major impact on separation efficiency. They utilize the principle of de-entrainment by centrifugal force to overcome the gravitational limitation of jet flooding, and the system limit of the vessel. Every set of ConSep tray consists of a primary tray (with chordal or HiFi downcomer layout) and a secondary tray with Swirl tubes. Shell HiFi Sieve trays with ConSep decks FRI VALIDATION FRI Validation Shell ConSep trays have been tested at FRI, in the iso-butane/n-butane system at 11bar. At least 50% higher capacity was observed over some other high performance trays, with a separation efficiency as high as 90% and capacity substantially exceeding the system limit of the column. Efficiency (%) Competitor HPT VGPlus Cs (m/sec) Cs (ft/s) 54 % ConSep Tray Cs: = Capacity factor based on superficial area Experience list of Shell ConSep trays: KEY AREAS OF APPLICATION Refinery: Main fractionators Olefins: Deethanizers, Depropanizers, Debutanizers, Superfractionators C2 and C3 Splitters Service Industry No. of columns Debutanizer Refinery 8 Depropanizer Refinery 5 Main fractionator Refinery 2 Naphtha splitter Refinery 1 Diesel HDT stripper Refinery 2 H2S stripper Refinery 1 C2 splitter Olefins 1 PO drying column Chemicals 1 C6 dryer Chemicals 1 Reformate Splitter Refinery 1 C2 Green Oil Scrubber Refinery 1 As of June

13 Case study - Revamp of FCC debutanizer to Shell HiFi Plus and ConSep trays A debutanizer was revamped from 2-pass chordal downcomer trays to high performance Shell trays. Improved feed quality, increased throughput and conversion at FCC unit led to increased feed rate and more LPG content to the Debutanizer. Revamp objective: Increase capacity by 15% C5 content in top stream < 0.6 vol% RVP of bottom LCN < 85 kpa Revamp solution: 15 HiFi Plus trays in rectifying section 15 ConSep trays in stripping section The column proven capacity after the revamp increased by 21%, exceeding the objective by 6%, with lower C5 content in the top (0.3 vol %versus 0.6 vol%) and lower RVP in LCN (77 kpa vs 85 kpa). Overall tray efficiency achieved was more than 86%, well above the tray efficiency of the first generation high performance trays used before revamp which was 69%. Case study - Debottlenecking of HGO pumparound with Shell ConSep trays Shell ultra high capacity ConSep trays were applied in the capacity constrained HGO pump-around section of a crude distillation unit in a refinery. This was the first application of ConSep trays in a CDU. The post revamp test run established the realization of the expected performance. Revamp objective: Increase capacity by 53% Maintain product specifications for Naphtha, Kero, LGO and HGO Main modifications: 3 Shell ConSep trays in HGO PA section 7 Shell HiFi trays in stripping section 1.3m Sulzer MellapakPlus 252.Y in wash section 16 Shell CS trays in other sections 13

14 Mechanical Features Non-welded tray support system In several revamp projects aimed to increase the separation stages of an existing column, the number of actual trays had to increase (e.g. 3-for-2, 4-for-3, or 5-for-4). To accomplish this, a mechanical design is required to avoid impact on the schedule of the plant's turn-around, and minimize cost as well. Sulzer has developed a mechanical solution enabling installation of the trays by reusing the existing tower attachments, without any direct welding to the tower wall, thus avoiding any post-welding heat treatment and/or hydraulic testing of the vessel. This technique consistently reduce the turnaround time by using this technique. Trays for heavy duty services In some applications, particularly those subjected to operating upsets leading to panel dislodgment, the trays must withstand higher than normal mechanical loadings, i.e N / m2 (1 psi) or even N / m2 (2 psi). In such cases, special features may be employed in the mechanical design: Through-bolting panel connection Shear clips Downcomer spreaders Explosion doors The following devices show in the illustration below are used: Expansion rings Expansion joints Vertical struts Downcomer adaptors Solid or lattice beams The system can be also used for other purposes: modify the geometry of existing downcomers, modify the number of passes; change the tray orientation; replace packing beds with trays. 2 psi uplift BDH tray equipped with through-bolting assembly, shear clips and explosion doors. Expansion ring Vertical strut Lip-Slot panel connection The Lip-Slot is an enhanced type of tray panel connection which allows for: safe and easy installation up to 30% less installation time less maintenance costs as it does not use any bolted connection same mechanical reliability as conventional connections The Lip-Slot is combined with universal clamps for the fixation around the tray periphery. Existing support ring Lattice beam Expansion joint 14

15 Services Computer-aided engineering (CAE): 3D models Upfront engineering and design play a crucial role in cost optimization. Sulzer has integrated all major mass transfer products into an in-house design tool, creating a global standard. Customers profit directly from the use of our internal CAE tool. Layout drawings supplied in the course of the engineering phase will show a 3D sketch of the equipment being designed, for an easy and fast checking by the customer. Natural frequency analysis for tray vibration phenomena In some critical applications and under specific operating conditions, vibration phenomena may be induced to the trays. Based on plant feed-back data and in-house knowhow, Sulzer has developed a design tool to check for the following two main parameters: Natural frequency of the tray panels, as a function of the geometry, the supports, and the material of construction. Vibration factor, as a function of the flow rates and physical properties of the streams being processed. Natural frequency analysis of a full tray Finite elements method (FEM) and computational fluid dynamics (CFD) Sulzer also employs other advanced design tools, for example verification of mechanical integrity and functionality using finite element and CFD analysis. Turn around and tower field services Sulzer s global manufacturing capabilities ensure fast delivery of any tray hardware and replacement tray parts, regardless of original supplier. These can be manufactured from existing drawings or damaged parts and supplied on site quickly to meet your turnaround schedules. Replacement hardware can be supplied on consignment in lockers or trailers for convenience. 15

16 E10504 en , Copyright Sulzer Ltd 2018 This brochure is a general product presentation. It does not provide a warranty or guarantee of any kind. Please, contact us for a description of the warranties and guarantees offered with our products. Directions for use and safety will be given separately. All information herein is subject to change without notice.